Process for breaking emulsions



:and' relatively soft waters or Weak brines. emulsification and subsequent demulsification under the to approximately 10,000, and

United States Patent-O PROCESS FOR BREAKING EMULSIONS Melvin De Groote, University City, and Bernhard Keiser,

Webster Groves, Mo., assignors to Petrolite Corporation, Wilmington, Del., a corporation of Delaware No Drawing. Application April 4, 1955, Serial No. 499,197

7 Claims. (Cl. 252341) The present invention relates to processes or procedures particularly adapted for preventing, breaking or resolving emulsions of the water-in-oil type and particularly petroleum emulsions.

. Our invention provides an economical and rapid process Y for resolving petroleum emulsions of the water=in-oil type that are comrnonly referred to as cut oil, roily oil, emulsified oil, etc., and which comprise fine droplets of naturally-occurring waters or brines dispersed in a more "or less permanent state throughout the oil which constitutes the continuous phase of the emulsion.

. It also provides an economical and rapid process for j separating emulsions which have been prepared under controlled conditions from mineral oil, such as crude oil Controlled conditions just mentioned are of signiificant value in reline oil.

. Attention is directed to our co-pending application Serial No. 499,196, filed April 4, 1955. In its broadest "aspect said co-pending application is concerned with a quaternary ammonium compound of the structure 1 in which n is a small whole number not over 4, and CR0 where (C3H60)y equals at least 10, and (CaH40)z+z' equals 10-90% of the total weight of the compound, the molecularweight being within the range of approximately 800 the radical of the halogenated monocarboxy acid having not over 18 carbon atoms in which n is a small .-satisfy the trivalent nitrogen valency, and R is a member I of the class selected from hydrogen and in which the characters have their previous significance.

I We have found that at least one sub-genus of the broad R genus described in our co-pending application, Serial No.

2,771,450 Patented Nov. 20, 1956 499,196 filed April 4, 1955, is particularly valuable for the resolution of petroleum emulsions. Thus, the present invention is dilferentiated from the invention of our copending application Serial No. 499,196, in that it is concerned with the use of a more narrow class of compound described therein, for the specific purpose of resolving petroleum emulsions.

More specifically the present invention is concerned with a process for breaking petroleum emulsions of the waterin-oil type characterized by subjecting the: emulsion to the action of a demulsifier including a quaternary ammonium compound of the structure U I: (pyridine) OHzC 0 R0 0 CH2 (pyridine) Cl 2 in which ORO is the residue of the oxyethylated polypropyleneglycol where (C3H60)y equals approximately 40% to 60%, and (C2H40)a:+a:' equals approximately 60% to 40% of the total weight of the compound, the molecular weight being within the range of approximately 2,000 to 4,000.

Much of the present text is approximately the same or in some ways a narrow description of the same subject matteras appears in aforementioned co-pending application, Serial No. 499,196, filed April 4, 1955. r

For purpose of convenience, what is said hereinafter is divided into fourparts:

Part 1 is concerned with the two initial reactants and their preparation, i. e., polyalkyleneglycols and the halo genated monocarboxy acid which in this instance is limited to monochloroacetic acid;

Part 2 is concerned With the preparation of esters by reaction between the two classes of reactants previously noted, i. e., the glycol and the acid;

Part 3 is concerned with the conversion of the ester by means of pyridine into a diquaternary compound, and Part 4 is concerned with the use of such compounds and the resolution of petroleum emulsions of the water-in-oil type.

PART 1 The preparation of the polyalkyleneglycols which are used as initial reactants, can be a continuous process in which water, propyleneglycol, or low molal propyleneglycol is oxypropylated by means of any suitable catalyst, either acid or alkaline, and then subjected to oxyethylation. Instead of being a single step process, one may employ a two-step process in which oxypropylation takes place first and then oxyethylation. If desired, one can simply purchase a suitable polypropyleneglycol from any one of a number of sources and subject the product to oxyethylation as hereinafter specified. If desired, one can purchase the oxyethylated propyleneglycols in the open market and thus the first step is merely esterificatio'n, followed by the second step which involves conversion into a quaternary ammonium compound.

As has been stated previously, the polyalkyleneglycols employed are reactants obtained by the oxyethylation of polypropyleneglycol. In a general way, the composition of such polyalkyleneglycol is such that the molecular Weight range varies from 2,000 to approximately 4,000. The amount of ethylene oxide present in the compound as compared with the oxypropyleneglycol, varies from 10% to 20% up to approximately to- Indeed, this is the generally accepted procedure for the characterization of such product. Thus the table employed by one manufacturer is as follows in which the X marks indicate products regularly available and those available in carload or large quantities appear with specific designations other than an X mark.

IABLE I.-.NOMENCLA.TURE OF OXYE'IHYLATED POLYPROPYLENEGLYOOLS ETEYLENE OXIDE IN MOLECULE, PERCENT Seconddiglt' ,0-10 10-20 2030 -40 40-50 50-00 0 (1) (4) Molecular weight of base First The manufacture of ethyleneglycol, polyethyleneglycol, propyleneglycol, polypropyleneglycol, and oxyethylated poly/propyleneglycol, is well known. One procedure, of course, is to simply oxypropylate water so as to obtain the polypropyleneglycol of the desired molecular weight,

for instance, in the range of 1,000 or 1,200 or thereabouts, to approximately 2,500, or 3,000, and then to oxyethylate so as. to obtain an oxyethylated polypropyleneglycol coming within the indicated range.

j However, one need not start with water and one may start with a low molal water-soluble glycol, for instance,

- propylene, dipropylene or tripropyleneglycol.

I If desired,-or1e may purchase the polypropyleneglycol inythe open market. For instance, one manufacturer regularly manufactures polypropyleueglycol within the following three molecular weight classes, to wit, 400- Higher molecular:

450; .975-1075; and 1050-2100. weights are available-also, as for example, at least one product having a molecular weight of approximately 2750 or thereabouts. There are also being oifered currently polypropyleneglycols having molecular weights of approximately 3000 and 4000. Thus, if desired one can purchase a suitable polypropyleneglycol and not resort to oxypropylation at all. All that is required is to oxyethylate the polypropyleneglycol obtained in the open .market' or prepared to specification.

It is not believed that any description of the manufacture of such products is require-d but purely for purpose of illustration reference is vmade to U. S. Patent No.

2,674,619, dated. April 6, 1954, to Lundsted. In'said patentthere is .a characterization of such products in the following language:

18. Compounds having improved detergent properties, according to the formula i where y equals at least 15; and (C2H40)z+cc' equals 2090% of the total weight of the compound.

Y or the like, and although substantially the same there is a slight variation in composition. The reason is due to at least two factors. As pointed out previously one does not get a'single product but one obtains cogeneric 1025 to 1 12s in one case, and 1900 and 2150 in another case. The other factor is one that has been pointed out a number of times and particularly in a series of 'a secondary alcohol radical and since one can look upon polypropyleneglycols as polymeric linear condensation derivatives of propyleneglycol it is obvious one could obtain head-to-head polymerization, tail-to-tail polymerization, and head-to-tail polymerization. This simply means the equivalent of ether-ization involving '2 primary hydroxyl groups or 2 secondary hydroxyl groups, or a primary and a secondary hydroxyl group. This is illustrated by the fact that there are three dipropyleneglycols. If one goes to tripropyleneglycol there are theo' retically at least eight possibilities. In the higher polypropyleneglycols these possibilities increase enormously. Thus, the first variation is in the molecular Weight size which determines the average molecular weight and the second variation is concerned with the fact that dependent on the method of oxypropylation employed, and various factors such as catalyst used, temperature, pressure, speed of reaction, etc., there may be variations in the actual structure. For this reason solubility in water must be interpreted in light of such fact and, thus, although polypropyleneglycol of an average molecular weight of 1,000 or thereabouts may show solubility of about 1.5% inwater actually this may be the solubilityofsome of the low molal cogeners. Thus, it is customary to consider polypropyleneglycols having a molecular weight of 1,000 or more as being substantially water-insoluble. Such customary use is herein included. Even if the molecular weight is double, up to 2000 or 'the'reabo'uts', there'imay even be a trace of the glycol which is water soluble, for instance, somewhere in the neighborhood of .015%.

In subsequent Table 2 the polypropyleneglycols obtained variedin molecular weight from approximately 1100 to 3600. They were obtained as the equivalent of reacting one mole of water with 18 moles, 20 moles, 24

and 59 moles of propyleneoxide. They were then reacted with small amounts of ethylene oxide; in some mixtures whose average composition corresponds tothe I molecular weight indicated. For instance, one manufacturer of a p-olypropyleneglycol whose average molecular weight is 1025 states the molecular weight in fact varies-from 975 to 1075 and, similarly in the case of a product whose average molecular weight is 2025 the V variation runs from 1950 to 2100. Depending on the shown and also the percentageof the two oxides ignoring the initial moles of water.

TABLE II Ignoring initial mole Propy- Ethy- Molec. Melee. water Melee. wt. Ex. lene lene wt. conwt. conincluding N0. oxide, oxide, tributed tributed 1 mole moles moles by PrO by EtO Percent Percent water PrO EtO 18 1 1, 044 44 95. 96 4. 04 1, 106 18 2 1, 044 88 92. 23 7. 77 1, 150 18 3 1, 044 132 88. 77 ll. 23 1, 194 18 4 1, 044 176 85. 58 14. 42 1, 238 20 1 1, 160 44 96. 35 3. 65 1, 222 20 2 1, 160 88 92. 95 7. 05 1, 266 3 1, 160 132 89. 79 10. 21 1, 310 20 4 1, 160 176 86. 82 13. 18 1, 354 24 2 1, 392 88 94. 05 5. 95 1, 498 24 3 1,392 132 91.34 8. 66 1, 542 24 4 1, 392 176 88. 77 11. 23 1, 586 24 5 1, 392 220 86. 13.65 1, 630 28 2 t 1, 624 88 94. 87 5. 13 1, 730 28 3 1, 624 132 92. 48 7. 52 1, 776 28 4 1, 624 176 1 90. 22 9. 78 1, 820 28 5 1, 624 220 88. 09 11. 91 1, 864 32 3 1,856 132 93. 36 6.64 2, 006 32 4 1, 856 176 91. 33 8.67 2, 050 32 5 1, 856 220 89. 40 10. 2, 096 32 6 1, 856 264 87. 57 12. 43 2, 140 38 4 2, 204 176 92. 60 7. 40 2, 398 v 38 5 2, 204 220 90. 93 9. 07 2, 442 38" 6 2, 204 264 89. 3O 10. 2, 486 38 7 2, 204 308 87. 12. 25 2, 530 42 1 5 2, 436 220 91. 72 8. 28 2, 674 42 6 2, 436 264 90. 22 8. 78 2, 718 42 7 2, 436 308 88. 78 11. 22 2, 762 42 8 2,436 352 87.39 12.61 2, 806 46 6 2, 668 264 91. 00 9. 00 2, 950 46 7 2,668 308 89. 65 10. 35 2, 994 46 8 2, 668 352 88.35 11. 65 3, 038 46 9 2, 668 396 87. 09 12.91 3, 082 50 s 2, 900 352 80. 1s 10. 82 3, 270 50 9 1 2,900 396 87.99 12.01 3,314 50 10 2, 900 440 86.83 13. 17 3, 358 1 s0 11 2,900 484 35. 70 14.30 3,402 50 12 2, 900 528 84.60 15.40 3, 446 50 13 2, 900 572 83.52 16.48 3, 490 50 14 2, 900 616 82. 47 17. 53 3, 534 50 15 2, 900 660 81. 47 18. 53 8, 578

'1 As previously pointed out, having obtained an oxy- 180-195 C. to remove by distlllation 2 moles of water ethylated polypropyleneglycol of the kind described in or 36 grams. Xylene distilling over with the water was Table I which is available in the open market, or in the 40 separated and returned to the resin pot after removal of manner described in Table II, or variants thereof prothe water. A non-viscous amber colored water emulsivided, of course, they come within the molecular Weight fiable liquid resulted. v a limits previously set out, i. e., 2,000 to 6,000, and pr'ef- Further examples are illustrated in Table III, followerably 2,000 to 4,000, the next step is reaction with chloing:

TABLE III Moles 1 1 v Grams Moles Grams Ex. Diol 1 Moles Grams ehloro Grams Molar Temp., Time. H10 H 0 xylene No acetic ratio C hrs. 1 dis- 1 disused acid tilled tilled 2b- 4011---- l 3, 578 2 189 l-2 170 4% 36 2 l, 000 31)..." 13-88.. 1 3, 2 189 1-2 190 3 36 2 1, 000 4b L87 1 3, 650 2 189 1-2 176 8 36 2 1,000 50. 14-77- 1 3, 410 2 189 1-2 173-190 8 36 2 1, 000 6b- L-74- 1 3, 900 2 189 1-2 185-190 7% 36 2 1, 000 7b- 11-84- 1 4, 120 2 189 1-2 185-190 7% 36 2 1,000 8!; L-62- 1 2, 200 2 189 1-2 180 3 36 2 940 9b L-44- 1 2, 000 2 189 1-2 -170 8 36 2 650 1 Diols identified by number in the L series are from Table I; inthe small a series are from Table II.

roacetic acid. The acylchloride may be used but is more PART 3 expensive.

PART 2 Having obtained an ester 1n WhlCh there are two chlo- 5 rinated carboxy radicals obtained by reacting a diol of Esters are obtained by the usual esterificationprocedure the kind described i p 1 i 2 moles f mono- 111V01V1I1g f (11015 as descrlbed y? 1 Wlth mono chloroacetic acid as described in Part 2, such esters are chloroacetlc acid. The procedure is illustrated by the then reacted with pyridine t0 give a quaternary followlng examples: monium compound. Example 1b 70 One mole of oxyethylated polypropyleneglycol L-64 Example 10 (Table I) or 3000 grams was mixed with 1000 grams of One molecular equivalent of Example lb, or 4153 xylene in a resin pot with mechanical stirrer and Dean grams, was heated under reflux at 160 C. for one hour and Stark trap. Two moles of chloroacetic acid or 189 with 2 moles of pyridine or 158 grams. Upon cooling a grams were added and the mixture was heated to 75 homogeneous water-soluble material resulted.

in which R0 is. the residue'of propyleneglycol er examples are illustrated in Table IV followmg: 7

2. A process forv breaking petroleum emulsions of the water-in-oiltype, characterized by subjecting the emulsion TABLE IV 9 Molar Grams Molar Temp Ex. No Ester used equiv. Grams Moles ratio 0.

12:.20 1 4,131 158 '2 1-2 160 Ex.3b 1 4,308 158 2 1-2 160 1111.41: 1 4,803 158 2 1-2 160 Ex. 50 1 4, 563 15s 2 1-2 I 160 Ex. so 1 5,053 15s 2 1-2 160 Ex. 7b 1 5,273 15s 2 1-2 160 Ex.8b 1 3,293 158 2 1 1-2 1so Ex. 00 1 2, 303 15s 2 1-2 V 160 PART 4 to the action of a demulsifier .including a quaternary As has been pointed out previously, both the glycols herein described and the esters derived therefrom, are

suitable for the resolution of petroleum emulsions.

As to the use of the described glycols, reference is made j to the use of conventional demulsifying agents as in U. S. Patent No. 2,626,929, dated January 27, 1953, to De Groote, and particularly to Part 3. pears therein applies with equal force and effect to the Everything-that apherein described.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. A process for breaking petroleum emulsions of the I water-in-oil type, characterized by subjecting the emulsion f to the action of a demulsifier including a quaternary ammonium compound of the structure v o o Y [(pyrldlne)CHA J0ROgCH:(pyrldine)][Cl1 the oxyethylated polywhere (CaHsOh equals approximately 40%to 60%, and (Cal-140k equals approximately 60% to 40% of the total weight of the compound, the molecular weight being within the range of approximately 2,000 to 6,000.

ammonium compound of the structure in which 0R0 is the residue of the oxyethylated polywhere (C3H60)y equals approximately 40% to 60%, and (C2H4O)+1' equals approximately 60% to 40% of the total weight of the compound, the molecular weight being within the range of approximately 2,000 to 4,000.

3. The process of claim 2 wherein (CsHsOh equals approximately 60% and (CzH40)z+:r' equals approximately 40%.

4. The process of claim 2 wherein (CaHsOh/ equals approximately and (C2HiO)z+z' equals approximately 45%. l

5. The process of claim 2 wherein (CaHsOh-equals approximately 50% and (C2H4O):+=' equals approximately 50%.

6. The process of claim Z'Wherein (C:HaO) equals approximately 45% and (Cal-140k equals, approximately 55%.

7. The process of claim 2 wherein (Cal-I50) equals approximately 40% and C2H4O)+u equals approximately 9 De Groote et al Nov. 4, 1947 De Groote et a1. Apr. 17, 1951 Lundsted Apr. 6, 1954 

1. A PROCESS FOR BREAKING PETROLEUM EMULSIONS OF THE WATER-IN-OIL TYPE, CHARACTERIZED BY SUBJECTING THE EMULSION TO THE ACTION OF A DEMULSIFIER INCLUDING A QUATERNARY AMMONIUM COMPOUND OF THE STRUCTURE 